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Check out this old USAF film (split into two parts) documenting Project Streak Eagle, when a stripped-down, souped-up F-15A Eagle smashed eight time-to-climb records in the span of two weeks - and six of them in one day - in 1975 at Grand Forks AFB in North Dakota. Thanks to YouTuber shaunhill13 for the find and the post.

F-15 Streak Eagle

In 1975, the U.S. Air Force knew their then-brand new Eagle, first flown just two and a half years earlier, was a hot ship, but wanted to win a little bit of propaganda by showing off how hot it really was. What better way to prove that than by chasing down the standing time-to-climb records owned by two airplanes: the McDonnell-Douglas F-4 Phantom, which the Eagle replaced in the USAF inventory, and the Mikoyan-Gurevich MiG-25 Foxbat, which the Eagle was designed to beat out in the air superiority arena. The reason the Air Force could to do this was simple. The F-15 was the first combat fighter to have a thrust-to-weight ratio of greater than 1. The F-15A's two Pratt & Whitney F100 engines combined for almost 48,000 pounds of thrust with full afterburner, while a fully loaded Eagle itself weighed around 44,500 pounds. So theoretically, the Eagle didn't need its wings to go straight up. It should be noted that time-to-climb performance is arguably the most critical performance parameter for interceptors. After all, an interceptor is only as good as its ability to to meet high-flying enemy aircraft at a point as far from base as possible, in as little time as possible. This was the F-15's primary job. A full year before the Eagle entered service, the seventeenth Eagle produced was taken straight off the McDonnell-Douglas line and sent to Grand Forks AFB in North Dakota, where cold January weather would be favorable for record-breaking. Three pilots, Maj. Roger Smith, Maj. Dave W. Peterson, and Maj. William R. "Mack" MacFarlane were sent there with it and told to go re-write the record book.

F-15 Streak Eagle Pilots

The Eagle in question, No. 72-0119, was stripped of its radar, flaps, air brake, guns and fire control system avionics, and left unpainted in order to save weight - 1800 pounds worth compared to the garden variety F-15A, according to Joe Baugher. Operation Streak Eagle commenced in January 1975.

F-15 Streak Eagle in flight

To further optimize the Streak Eagle's weight for each flight, the plane was only loaded with as much fuel as it needed to make each record attempt. For takeoff, the plane was taxied to the end of the runway at Grand Forks and hooked up to a hold-back bar, as can be seen in the video. The pilot then throttled the engines to full afterburner, and at the precise moment, the bar was released, and the Streak Eagle launched. Even given the lightness of the airframe and the power of the engine, it's still remarkable to see how quickly the Eagle would lift off the runway after an incredibly short takeoff roll of about 400 feet. Between January 16 and February 1, Majors Smith, MacFarlane and Peterson would make good on their orders to re-write the time-to-climb record book eight times over. Among the highlights from the video:

The Streak Eagle knocked off five records in three flights in the span of six hours on the first day, January 16.

The second flight on that day broke three records: 6,000m, 9,000m and 12,000m.

The third flight reached 15,000m (just under 50,000 feet) in one minute, 17.2 seconds, which was a faster time to that height than the Saturn V rocket from the Apollo program.

On the final flight, to 30,000m (just over 98,000 feet) on February 1, Major Roger Smith pushed the Streak Eagle over the top at a maximum of just over 102,300 feet, in what the video calls a "nearly ballistic trajectory."

Anytime you can use the words "ballistic trajectory" when flying a fighter plane, you're doing something awesome. The film above is in two parts in the embedded playlist, and shows each of the six record attempts in real time, which is quite amazing to watch in itself. And the music is so 1970s.